In general, automatic cleaners clean the floor of houses or buildings while traveling the floor. A driving force for moving such an automatic cleaner may be generated by a driving motor. Here, since the floor is generally flat, the automatic cleaner may easily travel along the floor using the driving motor.
However, when a surface to be cleaned is inclined, but is not flat, that is, the automatic cleaner cleans a surface inclined upward in a traveling direction, the automatic cleaner may be limited in traveling.
Specifically, when a surface to be cleaned is a window of a building, the automatic cleaner may be very limited in use. Thus, windows should be manually cleaned by a user.
Furthermore, the number of high buildings is being significantly increased in recent years Due to the dangerousness of the cleaning of windows, it is very difficult to directly clean the windows by a resident of a high building. Thus, specialist companies that clean windows appear.
However, there is no automatic cleaner for automatically cleaning surfaces to be cleaned which are vertically or inclinedly disposed with respect to the ground such as windows.
Even though specialist cleaning companies clean windows, the workers should clean the windows while moving along the windows using a rope fixed to the roof of the building. Thus, there is a limitation that a large number of persons and appliances are required.
Moreover, when an area to be cleaned is large, portions that a worker does not approach may exist. In addition, the dangerousness with respect to safety accidents of workers may be increased.